Length and Pressure of the Reconstructed Lower Esophageal Sphincter is Determined by Both Crural Closure and Nissen Fundoplication

Laparoscopic Nissen fundoplication is comprised of: a wrap thought responsible for the lower esophageal sphincter function and crural closure performed to prevent herniation. We hypothesized gastroesophageal junction competence effected by Nissen fundoplication results from closure of the crural diaphragm and creation of the fundoplication. Patients with uncomplicated reflux undergoing Nissen fundoplication were prospectively enrolled. After hiatal dissection, patients were randomized to crural closure followed by fundoplication (group 1) or fundoplication followed by crural closure (group 2). Intra-operative high-resolution manometry collected sphincter pressure and length data after complete dissection and after each component repair. Eighteen patients were randomized. When compared to the completely dissected hiatus, the mean sphincter length increased 1.3 cm (p < 0.001), and mean sphincter pressure was increased by 13.7 mmHg (p < 0.001). Groups 1 and 2 had similar sphincter length and pressure changes. Crural closure and fundal wrap contribute equally to sphincter length, although crural closure appears to contribute more to sphincter pressure. The Nissen fundoplication restores the function of the gastroesophageal junction and thus the reflux barrier by means of two main components: the crural closure and the construction of a 360A degrees fundal wrap. Each of these components is equally important in establishing both increased sphincter length and pressure.